## Thinking Mathematically (6th Edition)

$A = \{x|x ∈ N$ and $6 \leq x \lt 10\}$ $B = \{x|x ∈ N$ and $9 \lt x \leq 13\}$ Expressed using the roster method: $A = \{6, 7, 8, 9\}$ $B = \{10, 11, 12, 13\}$ a. Those sets are equivalent as they have the same number of elements. b. Those sets aren't equal, as their elements are not all the same.